Feed arrangement for a combustion furnace

ABSTRACT

The lower open end of an upstanding supply chute communicates with the upper surfaces of two pairs of stepwise arranged and partly overlapping upper pushing members and lower supporting members for transferring to the same combustible material. The respective elements are upwardly inclined relative to the horizontal and towards the furnace inlet, and with the pushing elements reciprocable relative to the supporting elements towards and away from the furnace inlet so as to stepwise displace the combustible material from the support surfaces into the furnace.

United States atent Martin et al. June 6, 1972 FEED ARRANGENIENT FOR A [56] References Cited COMBUSTION FURNACE UNITED STATES PATENTS 2,331,907 10/1943 Harrington ..2l4/23 X 2,011,344 8/1935 Kelly ...l10/l09 Inventors; Johannes Ma -tin; Eri h W b b th Martin of Munchen, Germany Primary Examiner-Robert G Sheridan [73] Assigneez Josef Martin Feverungsbau GmbH, n .Mi h l S. Striker Munchen, Germany 221 Filed: Dec. 29, 1969 [57] ABSTRACT [21] Appl NO; 888,483 The lower open end of an upstanding supply chute communicates with the upper surfaces of two pairs of stepwise arranged and partly overlapping upper pushing members and [30] Foreign Application Priority Data lower supporting members for transferring to the same combustible material. The respective elements are upwardly 1968 Germany 18 17 436'2 inclined relative to the horizontal and towards the furnace in- 2 let, and with the pushing elements reciprocable relative to the [5 US. Cl ..214/23, 1 lO/l09, 198/221 Supporting elements towards and away from the furnace inlet [51] Int. Cl ..B65g 25/08, F23k 3/12 so as to Stepwise displace the combustible material from the 581 Field of Search ..214/23-, 198/59, 221, 226; Support Surfaces into the fumace 9 Claims, 2 Drawing Figures PATENTEDJUH s 1972 INVENTORY- lomuues Jo; Mflm BY Educ VEB2 ATTQRNEY FEED ARRANGEMENT FOR A COMBUSTION FURNACE BACKGROUND OF THE INVENTION The present invention relates to a feed device for feeding combustible material to large-type furnaces, in particular installations for the combustion of refuse.

It is known to arrange a feed device for feeding combustible material at the lower or discharge end of a supply chute of large combustion installations, and this feed device comprises a plurality of feeding or pushing members which are stepwise superpositioned and horizontally reciprocable relative to each other. The feeding or pushing members engage the combustible material, e.g. refuse, and push the same in spaced portions past the discharge edges into the combustion chamber of the furnace.

However, such conventional horizontally operating feeding or pushing members of the feed device have the inherent disadvantage that with the supply of combustible material with a moist or slippery composition, an undesired slippage of excessively large quantities of such combustible material into the furnace takes place, which, as a result, leads to serious breakdowns or other failures in the feed arrangement.

Also known is a feeding arrangement in which the feed device is arranged at the lower or discharge end of the supply chute and consists solely of a curved feeding or pushing member, and with a portion of the supply chute end which discharges into the furnace, somewhat upwardly inclined with respect to the furnace.

However, also with this arrangement, an uncontrollable slippage of moist or slippery combustibles into the furnace will take place for reasons that with a curved feeding or pushing member the feeding is effected from above.

Further known is a feeding arrangement in which a blowpipe table is arranged at the lower end of the supply chute and in inclined relationship with the furnace.

However, this arrangement has the disadvantage that the combustible material which impinges from above, cannot, without special measures, be advanced in direction of the furnace.

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above disadvantages and to provide a feed device which positively avoids undesired slippage or seepage of combustion material into the furnace independent of the angle of inclination of the supply chute with respect to the furnace and, which, also as regards moist or slippery combustibles, positively controls the periodic in-feeding of the material into the furnace.

Such a feed device or arrangement for feeding combustible material, eg refuse, to a combustion furnace comprises at least one upper pushing and at least one lower supporting cooperating element each having an upper surface in the region of the outlet of a supply chute and each being upwardly inclined with reference to the horizontal and towards a respective discharge edge of the elements and which faces toward the inlet of the combustion furnace. The lower supporting element is stationary and ofiset with reference to the upper pushing element in direction towards the inlet of the furnace and the upper pushing element is reciprocably supported on the upper surface of the lower element. A reciprocating member reciprocates the upper pushing element with respect to the lower supporting element towards and away from the discharge edge of the latter so as to displace material which has descended from the outlet of the supply chute onto the upper surface of the lower element towards and past the discharge edge of the latter and into the inlet of the furnace.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional ob jects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a vertical cross-sectional view of the present feed arrangement and illustrates the lower discharge end of a supply chute which communicates with the feed device according to the invention; and

FIG. 2 is a partial cross-sectional view of an embodiment of a pushing element according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. I, the feed arrangement shown is seen to be associated and cooperating with the lower or discharge end of a supply chute 1 for the supply of combustible material which is to be gradually or stepwise fed by the feed arrangement to a furnace 6,

The feed arrangement is seen to comprise a first upper inclined pusher member 2 which, in the direction indicated by the arrow 2', is lengthwise reciprocably movable relative to and with its sliding end supported on a stationary correspondingly inclined restraining element 3 fixedly connected with its one end to a stationary support beam 7. The fixed restraining element 3 which also serves as receiving table for receiving and accumulating the combustible material from the chute 1, in turn, is supported with its other free end on a correspondingly inclined second lower pusher member 2a which, like pusher member 2, is also lengthwise reciprocably movable, however, in this instance relative to both the fixed restraining element 3 and a fixed correspondingly inclined feed table 4 in the direction indicated by the arrow 2". The pusher member 2a with its free or pushing end 2b is supported on the table 4 which at its one end 4a is fixedly supported to at least one support beam 7 and with its other or discharge end 5 is supported by the structural wall 12 of a furnace 6 with which the discharge end 5 communicates in order to feed combustible material received on the table 4 to the furnace 6.

The table 4 may be in the form of a grate having a plurality of bars, or the like, through which non-solids of the combustible material may be discharged and/or through which dry air, or the like, may be supplied to the combustible material.

In case table 4 forms a grate, the individual bars are supported by the support beam 7 and the wall 12.

The end portion 20 of the second pusher member is seen to be coupled to a sliding carriage 8 which, in turn is movably coupled to the first pusher member 2 and, thus, forms a connecting arm between the two pusher members.

Shifting of the first pusher member 2 takes place in response to abutment of an abutment member 8a on the carriage 8 with the first pusher member 2, Le, the carriage 8 is movable in a first direction in which the second pusher member 2a pushingly engages the combustible material on the table 4 and in which direction the abutment member 8a engages the shoulder portion 2d of the first pusher member 2 so as to cause the latter to move in corresponding direction in which it pushingly engages the combustible material on the receiving table 3, and the carriage 8 is movable in a second opposite direction in which it slides toward the end 4a of the table 4 and in which direction the abutment member 8a engages the abutment 2e which is a nut and is threadably received on the threaded end of an adjustable spindle 2f. This latter engagement of the abutment member 8a with the nut 2e causes the first pusher member to slide in the same direction as the second pusher member 2a and in which it slides towards the end 3a of the table 3.

As shown, the nut 2e is spaced apart at an adjustable distance from the shoulder 2d and, consequently, the two pusher members 2 and 2a are driven reciprocably relative to each other such that after a predetermined free stoke of the second pusher member 2a, the latter will shift the first pusher member 2 in corresponding direction.

The carriage 8 may be conveniently driven by the driving roller members 9 which, simultaneously, support the carriage.

Adjustment of the free stroke of the second pusher member 2a is effected by varying the distance between the nut 2e and the shoulder 2d by means of the adjustable spindle 2f.

A scraper is provided to scrape off the material possibly adhering to the upper surface of the first pusher member 2. This scraper 10 is self-adjustable and movable over the surface of the first pusher member 2.

According to the invention, the respective pusher members and tables are stepwise superimposed relative to each other and at an inclined angle relative to the horizontal in ascending relationship relative to the furnace 6.

This ensures that combustible material, supplied by the supply chute l and received on the table 3, as a result of the given angle of inclination a of the table relative to the horizontal, is retained on the former until the'pushing end of the first pusher member 2 engages and pushes the material from the table 3 towards the table 4 where it is received.

The same applies to table 4. Due to its corresponding angle of inclination, table 4 retains the combustible material until the latter is pushed over the discharge end 5 towards the furnace 6 by the second pusher member 2a.

It will be appreciated that the combustible material, in the abovedescribed manner, is discharged from the feed arrangement and fed to the furnace in measured quantities and at desired time intervals.

The stationary restraining element or table 3, in effect, serves the purpose, at the one hand, to avoid sliding back of the combustible material already advanced by the first pusher member 2 toward the furnace inlet and, at the other hand, to avoid undesirable sliding movement of the first pusher member 2 which would be the case if the table 3 were slidable and would slide under the weight of combustible material received thereon and would transmit this motion to the first pusher member 2 supported thereon.

As shown in FIG. 2, provisions are made to vary the angle of inclination of the respective elements 2,3,2a and 4 relative to the horizontal such as to adapt the same to a given composition of the combustible material.

Such a variation of the angle of inclination may, for example, be accomplished by elevating the pusher member 2, 24 by means of sliding blocks 1 l, or the like. Also, and depending on the requirements, one or more of the elements may be individually elevated by means of, for example, the sliding blocks 11 so as to give this respective element a greater angle of inclination than the remainder of the elements.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a feed arrangement for a combustion furnace, it is not intended to be limited to the details shown, since various modifications and structural changesmay be made with departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A feed arrangement for feeding combustible material into an inlet of a furnace comprising, in combination, a substantially upright supply chute having a lower open end for the issuance of material to be advanced to said inlet; and feed means arranged below said open end of said chute for gradually advancing to said inlet material issuing from said lower end, said feed means comprising a plurality of stepwise superimposed elements each having an upper surface facing said lower open end and being upwardly inclined toward said inlet, and a front wall extending transverse to said upper surface and facing said inlet, means stationaryly supporting every second of said su rimposed elements and means for reciprocating the 0 er elements relative to said stationanly supported elements for pushing material which has been descended from said open end of said chute onto the upper surface of the respective element into said inlet of said furnace.

2. A feed arrangement as defined in claim 1, wherein said feed means comprise four stepwise arranged superimposed elements in which the front walls thereof are offset in direction toward said inlet, and wherein said reciprocating means is connected only to the uppermost of said elements and to the third element immediately above the lowermost of said elements said support means stationarily support said lowermost element and the element sandwiched between said reciprocating elements.

3. A feed arrangement as defined in claim 2, wherein the individual angles of inclination of the respective elements are adjustable by means of sliding elevating attachment members connected to the elements and slidably supported by the upper surface of the next adjacent element.

4. A feed arrangement as defined in claim 1, wherein each of said front walls has a lower end, and wherein the lower end of the front wall of each element with the exception of the lowermost element abuts against the upper surface of the next lower element.

5. A feed arrangement as defined in claim 2, wherein said reciprocating means comprises a carriage reciprocable for a predetermined stroke and having a front end fixedly connected to said third element, and cooperating means in the region of the other end of said carriage and on said uppermost element for reciprocating the latter through a stroke smaller than said predetermined stroke of said carriage.

6. A feed arrangement as defined in claim 5, wherein said cooperating means comprise a pair of abutment faces spaced in the direction of the reciprocation of said carriage from each other and connected to said uppermost element for movement therewith and an abutment member fixed to said carriage and projecting between said abutment faces so as to abut against one of said faces during movement of said carriage in one direction and against the other of said faces during movement of said carriage in the opposite direction.

7. A feed arrangement as defined in claim 6, and including means for changing the distance between said abutment faces.

8. A feed arrangement as defined in claim 1, wherein said upper surfaces of said elements extend at individually different angles of inclination relative to the horizontal.

9. A feed arrangement for feeding combustible material into an inlet of a furnace, comprising, in combination, a substantially upright supply chute having a lower open end for the issuance of material to be advanced to said inlet; feed means arranged below said open end of said chute for gradually advancing to said inlet material issuing from said lower end, said feed means comprising a plurality of stepwise superimposed elements each having an upper surface facing said lower open end and being upwardly inclined towards said inlet, and a front wall extending transverse to said upper surface and facing said inlet, and means for reciprocating said elements relative to each other for pushing material which has been descended from said open end of said chute onto the upper surface of the respective element into said inlet of said furnace; and means selectively connectable to said elements for changing the angle of inclination of the respective upper surface relative to the horizontal. 

1. A feed arrangement for feeding combustible material into an inlet of a furnace comprising, in combination, a substantially upright supply chute having a lower open end for the issuance of material to be advanced to said inlet; and feed means arranged below said open end of said chute for gradually advancing to said inlet material issuing from said lower end, said feed means comprising a plurality of stepwise superimposed elements each having an upper surface facing said lower open end and being upwardly inclined toward said inlet, and a front wall extending transverse to said upper surface and facing said inlet, means stationaryly supporting every second of said superimposed elements and means for reciprocating the other elements relative to said stationarily supported elements for pushing material which has been descended from said open end of said chute onto the upper surface of the respective element into said inlet of said furnace.
 2. A feed arrangement as defined in claim 1, wherein said feed means comprise four stepwise arranged superimposed elements in which the front walls thereof are offset in direction toward said inlet, and wherein said reciprocating means is connected only to the uppermost of said elements and to the third element immediately above the lowermost of said elements said support means stationarily support said lowermost element and the element sandwiched between said reciprocating elements.
 3. A feed arrangement as defined in claim 2, wherein the individual angles of inclination of the respective elements are adjustable by means of sliding elevating attachment members connected to the elements and slidably supported by the upper surface of the next adjacent element.
 4. A feed arrangement as defined in claim 1, wherein each of said front walls has a lower end, and wherein the lower end of the front wall of each element with the exception of the lowermost element abuts against the upper surface of the next lower element.
 5. A feed arrangement as defined in claim 2, wherein said reciprocating means comprises a carriage reciprocable for a predetermined stroke and having a front end fixedly connected to said third element, and cooperating means in the region of the other end of said carriage and on said uppermost element for reciprocating the latter through a stroke smaller than said predetermined stroke of said carriage.
 6. A feed arrangement as defined in claim 5, wherein said cooperating means comprise a pair of abutment faces spaced in the direction of the reciprocation of said carriage from each other and connected to said uppermost element for movement therewith and an abutment member fixed to said carriage and projecting between said abutment faces so as to abut against one of said faces during movement of said carriage in one direction and against the other of said faces during movement of said carriage in the opposite direction.
 7. A feed arrangement as defined in claim 6, and including means for changing the distance between said abutment faces.
 8. A feed arrangement as defined in claim 1, wherein said upper surfaces of said elements extend at individually different angles of inclination relative to the horizontal.
 9. A feed arrangement for feeding combustible material into an inlet of a furnace, comprising, in combination, a substantially upright supply chute having a lower open end for the issuance of material to be advanced to said inlet; feed means arranged below said open end of said chute for gradually advancing to said inlet material issuing from said lower end, said feed means comprising a plurality of stepwise superimposed elements each having an upper surface facing said lower open end and being upwardly inclined towards said inlet, and a front wall extending transverse to said upper surface and facing said inlet, and means for reciprocating said elements relative to each other for pushing material which has been descended from said open end of said chute onto the upper surface of the respective element into said inlet of said furnace; and means selectively connectable to said elements for changing the angle of inclination of the respective upper surface relative to the horizontal. 